Lectrosonics D4 System

Q I was recently hired to provide location sound for a new reality television pilot. I have a sound-cart-based system I’ve successfully used on features for years, but this will be my initiation into reality television. The producer has made it clear that she needs four-channel audio feeds to each camera to save the labor of syncing external sources in post, although they want me to also include backup digital recording, which I can provide with my Sound Devices 788T. What recommendations do you have for wireless hops to two cameras?
Edward S.
Via email

A As the popularity of the reality television genre has continued to grow and prosper, sound mixing for reality television has evolved into a very distinct set of requirements. While the needs of different projects can vary, reality sound mixing typically requires many channels of wireless microphones. It can be a full-time job just wiring up talent, adjusting antennae and lavalieres, and replacing batteries, much less mixing audio. Then you would typically need additional channels of wireless to output the signal of your mixer and/or recorder to multiple cameras. On top of all of these requirements, reality television often requires frequent location moves and working in very tight spaces, so a bag-based system is usually preferred over a sound-cart-based system.

One of the more interesting pieces of gear that I’ve recently seen used on reality television sets is the Lectrosonics D4 Digital Wireless System (www.lectrosonics.com). The D4 is a four-channel digital/analog wireless audio system and was created to address specific interface and workflow challenges that often come into play when working on reality sets. Based upon feedback from sound mixers I’ve interviewed, the D4 system accomplishes these goals admirably. The advantages of the D4 system include the following:

Digital/Analog Agnostic: One of the challenges today’s sound mixer faces is that we’re in the era of digital transition, but often have to integrate analog devices with a digital workflow. Today’s sound mixers often need to integrate analog wireless microphone systems with digital recorders, digital/analog hybrid wireless sys-tems with analog mixers, analog mixer outputs with cameras, and digital recorders with both digital and analog inputs.

One of the most popular cameras used for reality programming is Panasonic’s AJ-HDX900, a tape-based HD camera that features four analog audio inputs. Conversely, the Sony HDW-790 also is quite popular on reality sets, but it features four AES/EBU digital audio inputs. The D4 system neatly skirts these issues because it features four channels of digital or analog inputs and four channels of digital or analog outputs. This means that you can input or output just about any type of signal—analog or digital—that you’ll need to transmit to the cameras.

Mitigating Many Frequency-Spectrum Issues: Depending on where you work in the world, wireless spectrum availability and restrictions may or may not affect you. Frequency-spectrum allocation is primarily an issue for sound mixers working in the U.S. In the U.S., recent FCC rulings and the changeover to digital television over the past few years have reduced the amount of UHF frequency spectrum available to wireless microphone users. There has been continuing concern about the future of wireless-spectrum availabil-ity for wireless systems, since a large portion of the spectrum, known as “white space,” was recently given to various wireless device manufacturers.

The D4 cleverly bypasses these restrictions because it’s an all-digital system that uses the license-free ISM band between 902 and 928 MHz. Unlike the UHF band, this portion of the spectrum is only 26 MHz wide (as opposed to over 230 MHz for UHF). The FCC considers the ISM band to be license-free, but still puts restrictions in place on how much power transmitters can have and how much bandwidth they can occupy. So while you’ll still have to deal with spectrum issues with analog wireless microphone systems on your talent, using the D4 to run your sound from your mixer/recorder to the cameras should be relatively trouble-free. You should be aware, though, that wireless DMX systems for stage lighting also use the ISM spectrum, so when shooting at live events with more sophisticated lighting setups, test to make sure your D4 system and the DMX system don’t interfere with each other’s operation.